1. Field of the Invention
The present invention relates to a semi-conductor device comprising a semiconductor chip on which electronics circuitry is formed into an integrated circuit (IC) and a package enclosing the semiconductor chip therein.
2. Description of the Background Art
The type of package molded with synthetic resin, electrically insulative, for enclosing an integrated circuit therein is advantageous in compactness and easy handling. A sort of synthetic resin package for an integrated circuit is known as the thin small outline package (TSOP). The thin small outline package includes a semiconductor chip having a primary surface on which contact pads are formed and in parallel to which connector leads extend outwards with the end portion thereof, nearer to the contact pads, secured on the primary surface by means of electrically insulative, adhesive strips. The contact pads are connected by bonding wires with the connector leads. The connecting portions of the bonding wires and the connector leads are encapsulated and sealed by a synthetic resin package together with the entire semiconductor chip. The electronics circuitry formed on the semiconductor chip is interconnected to the contact pads, which are electrically interconnected to the connector leads through the bonding wires. The electronics circuitry may ultimately be interconnected to a utility device, which will be coupled to the connector leads.
With the type of comiconductor device mentioned above, the bonding wires bonded to the contact pads formed on the primary surface of the semiconductor chip and the ends of the connector leads have such a sufficient length as to form an arc between the contact pads and the bonded ends of the connector leads. The bonded end portions of the connector leads are at the height, from the primary surface of the semiconductor chip, which height is substantially equal to the sum of the thickness of the adhesive strip and the thickness of the connector lead. The arcuate portion of the bonding wires extends over the height. That part of the synthetic resin package which covers the bonded end portions of the connector leads and the contact pads has to be of the thichness which is sufficiently longer than the height of the peak of the arc from the primary surface of the semiconductor chip. That requirement is a hindrance to minimizing the thickness of the synthetic resin package of a semiconductor device, and hence producing a compacter, or thinner, semiconductor device.